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Evaluating Metal-Ligand Interactions of Metal-Binding Isosteres Using Model Complexes
Hyeonglim Seo1, Kathleen E Prosser1, Mark Kalaj1
1Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, United States.
Inorganic Chemistry
|October 26, 2021
Summary
Bioinorganic model complexes reveal how metal-binding isosteres (MBIs) interact with metal ions, offering insights for designing new metalloenzyme inhibitors in fragment-based drug discovery.
Area of Science:
- Bioinorganic chemistry
- Medicinal chemistry
- Drug discovery
Background:
- Bioisosteres improve drug properties by addressing pharmacokinetic issues.
- Metal-binding isosteres (MBIs) combine metal-binding pharmacophores with bioisosteres for fragment-based drug discovery.
- Picolinic acid MBIs show potential but lack detailed characterization with various metal ions.
Purpose of the Study:
- To investigate the structural, electronic, and spectroscopic properties of picolinic acid MBIs and related compounds with Ni(II) and Co(II) metal ions.
- To establish bioinorganic model systems for studying MBIs.
- To compare MBIs with parent metal-binding pharmacophores.
Main Methods:
- Synthesis and characterization of [M(TPA)(MBI)]+ and [(TpPh,Me)Co(MBI)] complexes (M = Ni(II), Co(II)).
- Techniques included X-ray crystallography, NMR, IR, UV-vis spectroscopy, and magnetic moment measurements.
- Evaluation of two distinct bioinorganic model systems.
Main Results:
- Detailed characterization of picolinic acid, four heterocyclic MBIs, and 2,2'-bipyridine within Ni(II) and Co(II) complexes.
- Magnetic moments and spectroscopic data provided insights into metal-ligand interactions.
- Comparison of two model systems highlighted their respective advantages and limitations.
Conclusions:
- Bioinorganic model complexes are effective tools for studying metalloenzyme inhibitor design.
- The study provides a foundation for understanding the broader applications of MBIs in drug discovery.
- Results offer insights into the behavior of MBIs with different metal ions beyond Zn(II).
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